Treatment of hydrocarbons



Allg- 16, 1960 DUBOIS EASTMAN rs1-AL 2,949,420

TREATMENT OF HYDROCARBONS Filed NOV. 17, 1958 TREATMENT or HYDaocARnoNs Du Bois Eastman, Whittier, and Warren G. Schlinger,

Pasadena, Calif., assignors to Texaco Inc., a corporation of Delaware Filed Nov. 17, 1958, Ser. No. 774,218

18 Claims. (Cl. 20S- 70) This invention relates to the conversion of hydrocarbons. More particularly, it relates to the production of motor fuels of high octane number.

In one embodiment of the invention a crude petroleum oil is fractionated into a light straight run fraction boiling up to about 200 F., a heavy straight run fraction boiling from about 200 to about 400 F. and a residual fraction boiling above about 400 F. The residual fraction is subjected to highly turbulent flow in the presence of hydrogen at elevated temperatures and pressures to convert a substantial portion thereof to naphtha, the naphtha so produced being combined with the heavy straight run naphtha and the combined stream being catalytically reformed, part of the hydrogen necessary for the reforming being supplied from the hydrogen produced by the partial combustion of a portion of the balance of the turbulent ilow hydrogenation product. The reformed naphtha is combined lwith the light straight run naphtha to produce a motor fuel of high octane number.

In a more specic embodiment of the invention a crude petroleum oil is fractionated into a light straight run naphtha boiling up to about 200 F., a heavy straight run naphtha boiling from about 200 to about 400 F., a gas oil boiling between about 400 and 700 F. and a residual fraction boiling above about 700 F. The residual fraction is subjected to highly turbulent ilow in a hydrogenation zone in the presence of hydrogen to convert a substantial portion thereof to naphtha which is combined with the heavy straight run naphtha and a naphtha produced by the cracking of the gas oil. The combined naphtha stream is then catalytically reformed, part of the hydrogen necessary for the catalytic reforming being supplied from the hydrogen produced by the partial combustion of a portion of the balance of the product of the turbulent iiow hydrogenation.

For a better understanding of the invention, reference is now made to the accompanying drawing which illustrates diagrammatically a flow scheme for the practice of the present invention.

A full range crude petroleum is introduced through line 21 into fractionator 22 from which a light straight run naphtha boiling up to 190 F. is removed through line 23, a heavy straight run naphtha boiling up to 390 F. is removed through line 24, a gas oil boiling up to 700 F. is removed through line 25 and a residual fraction boiling above 700 F. is removed through line 26. The residual fraction together with hydrogen from line 31 is introduced into hydrogenation zone 32 which is maintained at a temperature of 925 F., a pressure of 3000 p.s.i.g. and a turbulence level of 165. The hydrogen is introduced from line 31 at a rate of 3000 s.c.f./bbl. of liquid feed. The mixture is passed under conditions of highly turbulent ow through hydrogenation zone 32 which is in the form of a tubular conduit having a length at least 100 times its radius.

In the hydrogenation step of this invention, the ow of materials in the reaction zone is maintained at velocities States Patent O rpice high enough to effect the apolymeric hydroconversion of the liquid hydrocarbon. These velocities may be obtained by ilowing the reactants as a coniined stream through a coil or tubular conduit. By so doing the hydrogen is brought into intimate contact with the hydrocarbon thereby reducing the distance of solution or diiusion of the hydrogen into the hydrocarbon. As a result, when the hydrocarbon molecule is cracked there is suicient hydrogen present at the site of the cracking reaction to react with the active fragments formed by the cracking before the active fragments can inter-react to form polymers. In addition, because of the intimate mixture produced by the highly turbulent flow, the consumed hydrogen is immediately replaced by additional hydrogen at fthe site of the reaction so that there is no local depletion of hydrogen in the reaction zone. In other Words, under the conditions of highly turbulent ow, hydrogen is always present throughout the reaction zone in suflicient amounts to prevent the formation of polymers and coke.

When a liquid and a gas are flowing through the same conduit it is possible to have several types of flow. These types of ow are described by Baker in the Oil and Gas Journal, July 26, 1954, page et seq. and are designated as stratified, plug, slug, annular, bubble or froth .and dispersed or spray types of iiow. To effect the apolymeric hydroconversion in a system having a two phase iiow only the bubble or froth or the dispersed or spray types of flow are satisfactory.

Hydrocarbon feed rate, hydrogen recycle rate, reaction coil diameter, and operating conditions of temperature and pressure all tend to affect velocity of ilow and turbulence. It has been found convenient to express turbulence in terms of the ratio of the average apparent viscosity of the owing stream, em, -to the molecular or kinematic viscosity v, viz.

if the magnitude of the apparent viscosity exceeds the kinematic viscosity at the point in question the ratio of exceeds unity. For a given turbulent system, it follows that the average value of the ratio, as expressed by exceeds unity. The average apparent viscosity, 2m, as employed herein is defined by the equation Where rg is the radius of the conduit. By substitution and integration, employing the parameters described by Corcoran et al., in Industrial and Engineering Chemistry, volume 44, page 410 (1952), this expression .J0 han im 15 20 dx The latter equation is in terms which may be readily determined for a given system.

may be rewritten Nomenclature d differential f g: acceleration of gravity, feet per second 2 i p=pressure, pounds per square'foot i r=radius of conduit, feet r=radial distance from center of conduit, feet x=distance, feet em=eddy viscosity, square feet per second i im: apparent viscosity, Square feet per second e m==average apparent viscosity, square feet per second ft=kinematic viscosity, square feet per second a: specific weight, pounds per cubic foot For effective apolymeric hydroconversion, the turbulence level is at least Z5. Turbulence levels of 50 to 1000 are preferred. Temperatures of 850 to 1600 F. may be employed. A preferred range of temperatures is from 950 to 1100n F. Pressures in excess of 1000 p.s.i.g. may be employed although pressures of 3000 to 10,000 p.s.i.g. are preferred. It is desirable for the hydrogenation gas to have a high hydrogen concentration but hydrogen concentrations as low as 25 volume percent may be used. Gas recycle rates of at least 1000 cubic feet per barrel of feed are employed and rates up to 100,000 cubic feet per barrel of feed may be used. Although reaction times of from one second to two hours may be employed, reaction times of l0 to 60 seconds are preferred.

The reaction product from hydrogenation zone 32 is transferred to high pressure separator 34 through line 33. Hydrogen separated from the reactionproduct :is recycled to hydogenation zone 32 by means of lines 31 and 26. The hydrocarbonaceous product is then transferred through line 35' to low pressure separator 36 from which the C1-C3 hydrocarbons are removed through line 40, a naphtha is removed through line 41 and a fraction boiling above 400 F is removed through line 42 and is sent to gas generation zone 43 through lines 44- and 45.

Gas generation zone 43 comprises a gas generator, a Waste heat boiler, a quench chamber, a shift converter and a scrubber. The 400 F.{- fraction with 150 pounds of steam and 3610 s.c.f. oxygen per barrel of hydrocarbon feed is introduced into the gas generator Where it is converted by partial combustion into a gas containing hydrogen. Generally, any metals present in the original feed are concentrated in the heavy fraction Withdrawn from low pressure separator 36, and since mineral ashforming constituents are detrimental to the life of the refractory lining of the gas generator the gasification of the liquid portion is conducted under controlled conditions of conversion.

The heavy fraction is introduced into the reaction zone of the gas generator together with sulhcient free oxygen to react exothermically with the feed to autogenously maintain a temperature in the range of about 2200 F. to about 3200 F. and to convert not less than about 90 percent and not more than 99.5 percent of the carbon contained in the feed to carbon oxides. The extent of conversion of the carbon may be varied within thisrange depending upon the amounts of heavy metals contained in the feed. The quantity of unconverted carbon should be at least 50 times and preferably 10() times the combined Weights of the nickel and vanadium contained in the feed on the basis of the weight of the metal content of the metal-containing constituents present in the feed. The unconverted carbon from the hydrocarbon is liberated as free carbon. Under these conditions of limited carbon conversion, the ash-forming constituents of the feed, particularly the ash resulting from the heavy .6 p.s.i.g. in cracking unit o1.

metal constituents, are associated with the carbon and the composite is liberated as carbonaceous solid in particle form. The carbonaceous solid particles containing the heavy metals are substantially harmless to the refractory lining of the gase generator.

More specifically, the liquid feed containing mineral ash-forming constituents including nickel and vandium is admixed with steam and fed into a compact, unpacked reaction zone. The reaction zone is free from packing and catalyst and has an internal surface area ofnot more that 1.5 times the surface of a sphere equal in volume to the lvolume of the reaction zone. An oxygen-rich gas containing about 95 percent oxygen by volume is introduced into the reaction zone Iinto intimate admixture with the feed and steam. The generator may be operated at atmospheric or superatmospheric pressure. Preferably the generator is operated at a pressure within the range of from about y100 to about 600 p.s.i.g. The temperature within the gas generator is autogenously maintained preferably within the range of 2500 to 2900 F.

The quantity of free oxygen supplied to the gas generator is limited so that the conversion of carbon to carbon oxides is limited to to 99.5 percent of the carbon content of the oil fed to the gas generator. From about 1.8 to about 1.9 mols of free oxygen are supplied to the gas generator for each million B.t.u.s gross heating value lof the feed to the gas generator.

The amount of unconverted carbon released as a carbonaceous solid in the gas generator should be at least 50 times by weight the combined weights of the metals including nickel and vanadium contained in the feed based on the weight of the free metal content of the metal-containing compounds in the feed. Free carbon released in the gas generator is entrained in the gaseous products of reaction. Ash from the fuel, particularly the heavy metal constituents, is substantially completely retained in the carbonaceous residue. The -hot gases from the generator containing entrained carbon are lirst passed through a waste heat boiler and then contacted with Water in a gas scrubbing and quenching operation. The carbonaceous solid is removed from the gas stream in the scrubbing operation.

If desired, the scrub water containing suspended carbon particles is contacted with a portion of the liquid feed to the gas generation zone. The carbon particles are preferentially wetted and taken up by the liquid hydrocarbon 'which is then introduced into the gas generator. In this way, the carbon can be recycled to extinction.

To produce a hydrogen-rich gas, the gaseous products from the partial combustion are cooled by indirect heat exchange to a temperature of about 230-240 F. and are mixed with steam to provide a 4 or 5 to l Water to CO ratio. The mixture is passed over an iron oxide catalyst in a reactor containing three intercooled beds. The mixture is introduced into the reactor at a temperature of about 700 lF. In the iirst bed the temperature rises to about 850 F. The gases are then cooled to a temperature of about 720 F. prior to passage through a second bed wherein a temperature rise of about 30 F. is eifected. The gases are then cooled to a temperature of about 680 to 700 F. before introduction into the third bed where very little temperature rise occurs. The gases are then cooled to 100 R to allow the Water to separate out and are then passed through an amine scrubber in which the lCO2 is absorbed. The scrubbed gashas a hydrogen content of about volume percent.

The hydrogen-rich gas is removed from the gas generation zone 43 through line 50 and a portion thereof is sent to hydrogenation unit 32 through lines 52, 31 and Z6.

The gas oil removed from fractionator 22 through line 25 is contacted with a fluidized silica alumina catalyst at a temperature of 910 F. and an average pressure of The space velocity is 2.4 Weight of oil per hour per Weight of catalyst and the catalyst to oil ratio basis `fresh feed is 7.7. Other catalysts such as silica magnesia or activated clay may be used in the cracking unit. Depending on the catalyst,

the temperatures may vary from 850-l100 F. and the average pressures from -l6 p.s.i.g. The catalyst to oil ratio may range from 2-15 volumes of oil per volume of catalyst and the space velocity may range from 1-3 weight of oil per hour per weight of the catalyst. rIlhe cracked product is removed through line 62 and introduced into separator 63 from which a C1C3 fraction is removed through line 64, naphtha is removed through line 65 and unconverted gas oil removed through line 66. A portion of the unconverted gas oil is recycled to cracking unit 61 through lines 70 and 25 and the balance is withdrawn from the system through line 71.

The naphthas in lines 41 and 65 are combined with the heavy straight run naphtha in line 24 and with hydrogen from line S0 are introduced into hydrodesulfurization unit 75 where the combined stream is contacted with a cobalt molybdate on alumina catalyst at a temperature of 700 F., a pressure of 500 psig., a space Velocity of 3 volumes of naphtha per volume of catalyst per hour and a hydrogen rate of 3000 s.c.f./bbl. Suitable othery catalysts which may be used in the hydrodesulfurization unit are cobalt molybdate on alumina-silica or nickel tungsten sulde. The severity of the operating conditions may vary depending upon the amount of sulfur present in the naphtha and the extent of desulfurization desired. For example, temperatures may range from 400-850 F., pressures from 50 to 1500 p.s.i.g., space velocities from 0.5 to 20 and hydrogen rates from 250 to 6000 s.c.f./bbl.

Eiuent from hydrodesulfurization zone 75 is sent through lines 76 and 77 to stripping unit 78 where hydrogen, H28 and Cl-Ca hydrocarbons separated from the desulfurized naphthas are removed through line 79. The naphtha is then sent with hydrogen from line 39 through line 81 to catalytic reforming unit 82 where it is contacted with a platinum alumina catalyst at a temperature of 950 F., a pressure of 500 p.s.i.g. and at a space velocity of 3.0 v./v./hr. in the presence of 7000 soli/hydrogen per barrel of naphtha feed. Depending on the octane number desired the operating conditions may be varied, for example, temperatures may range from 800-1000 F., pressures from 50-750 p.s.i.g., the space velocity from 0.7 to 5.0 v./v./hr. and the hydrogen from 4000 to 8000 s.c.f./bbl. Suitable other catalysts are platinum on an alumina-silica base, platinum on alumina containing halogen or molybdena on alumina. The etliuent from catalytic reforming unit 82 is transferred through line 83 to high pressure separator S4 where hydrogen is separated from the reformate and is sent to hydrodesulfun'zation unit 75 through lines 80 and 24. The reformate which contains small amounts of normally gaseous hydrocarbons is then sent to low pressure separator 85 through line 86. The C1C3 hydrocarbons are removed through line 90 and the reformed naphtha through line 91 to be combined with light straight run naphtha from iline 23 and sent to gasoline storage.

Ilhe gaseous hydrocarbons removed from separator 85 through line 90 may be combined with similar streams removed from separator 63 through line 64 and low pressure separator 36 through line 40 yand subjected to partial combustion in gas generation zone 43 for the production of hydrogen. When the hydrogen produced by the pantial combustion of this C1C3 stream is suicient to supply the requirements of the system and no excess hydrogen is desired, as, for example, for the production of ammonia, the fraction boiling above 400 F. removed from low pressure separator 36 is recycled to hydrogenation unit 32 through lines 42 and 26. When large amounts of hydrogen are desired or needed, unconverted gas oil removed from separator 63 through line 66 may be sent through a line (not shown) to gas generation zone 43 for conversion to a gas rich in hydrogen.

IIn another embodiment of the invention the naphtha 6 removed from low pressure separator 36 through line 41 is separately desulfurized in hydrodesulfurizlation unit 94 to which it is introduced through line 93 together with hydrogen from line 96. The desulfurization conditions in hydrodesulfurization unit 94 may be less severe than those in hydrodesulfurization unit 75 as the product of turbulent iiow hydrogenation unit 32 is much more susceptible to desulfurization than are the straight run naphtha and/or the catalytically cracked naphtha. It is therefore possible to use a catalyst of lower activity in hydrodesulurization unit 94 than in hydrodesulfurization unit 7S. It is even possible to charge to hydrodesulfurizaf tion unit 94 a catalyst of reduced activity which has already been used in hydrodesulfurization unit 75 and which is no longer economically satisfactory for use for the desulfurization of the straight run or cracked naphtha or, in other words, is spent. This spent catalyst still has suiiicient activity to desulfurize the naphtha produced by the hydrogenation of turbulent ilow hydrogenation zone 32. Eifluent from hydrodesulfurization unit is then sent to stripper 78 through lines 92 and 77.

If desired, all of the crude boiling above 400 F. may be sent to hydrogenation zone 32 in which case, no gas oil fraction would be withdrawn from separator 22 through line 25. lt is `also possible, instead of recycling all or a portion of the gas oil from separator 63 to cracking unit 6l, to send all or a portion of the gas oil so separated to hydrogenation unit 32 through lines 70, 73 and 26.

Obviously, many modifications and variations of the invention @as hereinbefore set forth may be made without departing from the spirit and scope thereof, and therefore, only such limitations should be imposed as are indicated in the appended claims.

We claim:

l. A process for the production of motor fuel which comprises fractionating a cuide petroleum hydrocarbon liquid into a light fraction boiling below about 200 F., an intermediate fnaction boiling between about 200 and 400 F., and a heavy fraction boiling above about 400 F., subjecting at least a portion of said heavy fraction to conditions of highly turbulent flow in a hydrogenation zone in the presence of hydrogen at a temperature between about 850 and 1600 F. and 'a pressure in excess of 1000 p.s.i.g., recovering from the reaction product a liquid fraction boiling up to about 400 F. combining said liquid fraction with said intermediate fraction to produce -a combined naphtha stream, subjecting a portion of the balance of said reaction product fto partial combustion to produce a gas containing hydrogen, introducing at least a portion of the hydrogen so produced into said combined naphtha stream and passing the resulting mixture into Contact with a reforming catalyst at a temperature between about 800 and l000 F. and `a pressure between about 50 and 750 p.s.i.g. and combining the reformed liquid product with said light fraction to produce a motor fuel of high octane number.

2. The process in claim l in which a portion of the hydrogen produced by the partial combustion is introduced into the hydrogenation zone.

3. The process of claim l in which the turbulence level in the hydrogenation zone is at least 25.

4. The process of claim l in which the turbulence level in the hydrogenation zone is between 50 and 1000.

5. The process of claim 1 in which the reforming cartalyst comprises platinum on alumina.

6. A process for the production of -a motor fuel which comprises fractionating a crude petroleum hydrocarbon liquid into a light naphtha boiling up to about 200 F., a heavy naphtha boiling between about 200 and 400 F., a `gas oil boiling between about 400 and 700 F. and a residual yfraction boiling above about 700 F., contacting said gas oil fraction with a cracking catalyst at a temperature between 850 and 1l00 F., separating from the reaction product a normally gaseous `fraction and a liquid fraction boiling up to about 400 F., combining said liquid fraction with said heavy naphtha to produce a combined naphtha stream, subjecting said residual fraction to conditions of highly turbulent flow in a hydrogenation zone at a temperature between about 850 and 1600o F. and a pressure in excess of about 1000 p.s.i.g. in the presence of hydrogen, recovering from the eiiiuent from said hydrogenation zone a hydrogenated naphtha and a second residual fraction, introducing said hydrogenated naphtha fraction into said combined naphtha stream to produce a mixed naphtha stream, subjecting said second residual fraction to partial combustion to produce a gas containing hydrogen, introducing at least a portion of the hydrogen so produced together with said mixed naphtha stream into a catalytic reforming zone maintained at a temperature between about 800 and 1000 F. and a pressure between about 50 and 750 p.s.i.g., separating the effluent from the catalytic reforming zone into a gaseous fraction and a reformed naphtha and combining the reformed naphtha with said light naphtha to produce a motor fuel of high octane number.

7. The process of claim 6 in which the turbulence level in the hydrogenation zone is at least 25.

8. The process of claim 6 in which a portion of the hydrogen produced by the partial combustion is introduced into the hydrogenation zone.

9. A process for the production of a motor fuel which comprises fractionating a crude petroleum hydrocarbon liquid into a light naphtha boiling below about 200 F., a heavy naphtha boiling between about 200 and 400 F., a gas oil boiling between about 400 and 700 F. and a first residual fraction boiling above about 700 F., contacting said gas oil with a cracking catalyst at a ternperature between about 850 and 1100 F. separating from the reaction product a rst normally gaseous hydrocarbon fraction rand a liquid fraction boiling up to about 400 F., combining said liquid fraction with said heavy naphtha to produce a combined naphtha stream, subjecting said iirst residual fraction to conditions of highly turbulent ow in a hydrogenation zone at a temperature between about 850 and 1600 F. and a pressure in excess of about 1000 p.s.i.g. in the presence of hydrogen, recovering from the elfiuent from said hydrogenation zone a second normally gaseous hydrocarbon fraction, a hydrogenated naphtha and a second residual fraction, introducing said hydrogenated naphtha into said combined naphtha stream to produce a mixed naphtha stream, subjecting said second residual fraction to partial combustion to produce a gas containing hydrogen, introducing at least a portion of the hydrogen so produced together with said mixed naphtha stream into a catalytic reforming zone maintained at a temperature between about S and 1000 F. yand a pressure between about 50 and 750 p.s.i.g., separating the effluent from the catalytic reforming zone into a third normally gaseous hydrocarbon fraction and a reformed naphtha, combining said rst, second and third normally gaseous hydrocarbon fractions, subjecting the combined normally gaseous hydrocarbon stream to partial combustion with said second residual fraction and combining the reformed naphtha with said light naphtha to produce a motor fuel of high octane number.

10. A process for the production of a motor fuel which comprises fractionating a crude petroleum hydrocarbon liquid into a light naphtha boiling below about 200 F., la heavy naphtha boiling between about 200 and 400 F., a gas oil boiling between about 400 and 700 F. and a first residual fraction boiling above about 700 F., contacting said gas oil with a cracking catalyst at a temperature between about 850 and ll00 F. separating from the reaction product a first normally gaseous hydrocarbon fraction and a liquid fraction boiling up to about 400 F., combining said liquid fraction with said `heavy knaphtha to produce a combined naphtha stream,

subjecting said rst residual fraction to conditions of highly turbulent iiow in a hydrogenation zone at a temperature between about 850 and 1600 F. and a pressure in excess of 1000 p.s.i.g. in the presence of hydrogen, recovering from the eliuent from said hydrogenation zone a second normally gaseous hydrocarbon fraction, a hydrogenated naphtha and a second residual fraction, recycling said second residual fraction to said hydrogenation zone, introducing said hydrogenated naphtha into said combined naphtha stream to produce a mixed naphtha stream, subjecting said second normally gaseous hydrocarbon fraction to partial combustion to produce a gas containing hydrogen, introducing at least a portion of the hydrogen so produced together with said mixed naphtha stream into a catalytic reforming zone maintained at a temperature between about 800 and 1000 F. and a pressure between about 50 and 750 p.s.i.g., separating the eluent from the catalytic reforming zone into a gaseous fraction and a reformed naphtha and combining the reformed naphtha with said light naphtha fraction to produce a motor fuel of high octane number.

11. The process of claim 10 in which said first and said second normally gaseous hydrocarbon fractions are combined and then subjected to partial combustion to produce a `gas containing hydrogen.

12. A process for the production of a motor fuel which comprises fnactionating a crude petroleum hydrocarbon liquid -into a light naphtha boiling up to about 200 F. a heavy naphtha boiling between about 200 and 400 F., a gas oil boiling between about 400 and 700 F. and a residual fnaction boiling above about 700 F., contacting said gas oil with a cracking catalyst at a temperature between 850 and l F., separating the reaction product into a normally gaseous fraction and a liquid fraction boiling up to about 400 F., combining said liquid fraction with said heavy naphtha to produce a combined naphtha stream, subjecting said residual fraction to conditions of highly turbulent flow in a hydrogenation zone lat a temperature between about 850 and l600 F. and a pressure in excess of about 1000 p.s.i.g. in the presence of hydrogen, recovering from said hydrogenat-ion zone a hydrogenated naphtha, subjecting a portion of the balance of the hydrogenation zone reaction product to partial combustion to produce a gas containing hydrogen, introducing said combined naphtha stream into a first desulfurization zone containing a desulfurization catalyst and maintained :at a temperature between `about 400 and 850 F. and a pressure between 50 and 1500 p.s.i.g., introducing said hydrogenated naphtha into a second desulfurization zone containing a desulfurization catalyst and maintained at a temperature between about 400 and 850 F. and a pressure between about 50 and 1500 p.s.i.g., combining the desulfurized naphthas from said first desulfurization zone and said second desulfurization zone and contacting the combined desulfurized naphtha stream with a reforming catalyst in a reforming zone maintained at a temperature between about 800 and 1000" F. and a pressurev between 50 and 750 p.s.i.g., recovening reformed naphtha from the product of said reforming zone and combining said reformed naphtha with said light naphtha to produce a motor fuel of high octane number.

13. The process of claim A12 in rwhich the temperature and pressure in said second desulfurization zone are lower than the temperature and pressure in said first desulfurization zone.

14. The process of claim l2 in which the catalyst in said second Adesulfurization zone is spent catalyst removed from said rst desulfurization zone.

15. A process for the production of a motor fuel which comprises fractionating a crude petroleum hydrocarbon liquid into a light naphtha boiling up to about 200 F., a heavy naphtha boiling between about 200 and 400 F., a gas oil boiling between about 400 and 700 F. and a iirst residual fraction boiling above about 700 F., contacting said gas oil with a cracking catalyst at a temperature between about 850 and 1100 F., separating from the reaction product a normally gaseous fraction, a cracked naphtha and a second residual fraction, combining said rst and said second residual fraction and subjecting the combined residual fractions to highly turbulent ow in a hydrogenation zone in the presence of hydrogen at a temperature between about 850 and 1600" F. and a pressure in excess of about 1000 p.s.i.g., separating the reaction product into a second normally gaseous hydrocarbon fraction, a hydrogenated naphtha and a third residual fraction, recycling said third residual fraction to the hydrogenation zone, combining said iirst and said second normally gaseous hydrocarbon fractions and subjecting the combined stream to partial combustion to produce a gas containing hydrogen, combining the heavy naphtha, the cracked naphtha and the hydrogenated naphtha and introducing the combined naphtha stream with at least a portion of the hydrogen produced by the partial combustion into a catalytic reforming Zone at a temperature between about 800 and l000 F. and a pressure between about 50 and 750 p.s.i.g., separating a reformed naphtha from the reaction product and combining the reformed naphtha with said light naphtha to produce a motor `fuel of high octane number.

16. The process of claim l in which the turbulence level in the hydrogenation zone is at least 25.

17. The process of claim 15 in which the heavy naphtha and the cracked naphtha are passed through a rst catalytic desulfurization zone and the hydrogenated naphtha is passed through a second desulfurization zone and the desulfurized naphtha streams are combined prior to being catalytically reformed.

18. A process for the production of a motor fuel which comprises -fractionating a crude petroleum hydrocarbon liquid into a naphtha fraction, a gas oil and a residual fraction boiling above about 700 F., contacting said gas oil fraction with a cracking catalyst at a temperature between 850 and 1K100 F., separating from the reaction product a normally gaseous fraction and a liquid fraction boiling up to about 400 F., combining said liquid fraction with said naphtha fraction to produce a combined naphtha stream, subjecting said residual fraction to conditions of highly turbulent iiow in a hydrogenation zone at a temperature between about 850 and 1600 F. and a pressure in excess of about 1000 p.s.i.g. in the presence of hydrogen, recovering from the eluent from said hydrogenation zone a hydrogenated naphtha and a second residual fraction, introducing said hydrogenated naphtha fraction into said combined naphtha stream to produce a mixed naphtha stream, subjecting at least a portion of said second residual fraction to partial combustion to produce a gas containing hydrogen, introducing at least a portion of the hydrogen so produced together with said mixed naphtha stream into a catalytic reforming zone maintained at a temperature lbetween about 800 and l000 F. and a pressure between about and 750 p.s.i.g. and recovering from the eiiiuent from the catalytic reforming zone a motor fuel of high octane number.

References Cited in the tile of this patent UNITED STATES PATENTS 2,352,025 Seguy June 20, 1944 2,738,311 Prese et al. Mar. 13, 1956 

1. A PROCESS FOR THE PRODUCTION OF MOTOR FUEL WHICH COMPRISES FRACTIONATING A CRUDE PETROLEUM HYDROCARBON LIQUID INTO A LIGHT FRACTION BOILING BELOW ABOUT 200* F., AN INTERMEDIATE FRACTION BOILING BETWEEN ABOUT 200 AND 400* F., AND A HEAVY FRACTION BOILING ABOVE ABOUT 400* F., SUBJECTING AT LEAST A PORTION OF SAID HEAVY FRACTION TO CONDITIONS OF HIGHLY TURBULENT FLOW IN A HYDROGENATION ZONE IN THE PRESENCE OF HYDROGEN AT A TEMPERATURE BETWEEN ABOUT 850 AND 1600*F. AND A PRESSURE IN XCESS OF 1000 P.S.I.G, RECOVERING FROM THE REACTION PRODUCT A LIQUID FRACTION BOILING UP TO ABOUT 400*F. COMBINING SAID LIQUID FRACTION WITH SAID INTERMEDIATE FRACTION TO PRODUCE A COMBINED WITH SAID INTERMEDIATE FRACTION TO PROTHE BALANCE OF SAID REACTION PRODUCT TO PARTIAL COMBUSTION TO PRODUCE A GAS CONTAINING HYDROGEN, INTRODUCING AT LEAST A PORTION OF THE HYDROGEN SO PRODUCED INTO SAID COMBINED CONTACT WITH A REFORMING CATALYST AT A TEMPERATURE BECONTACT WITH A REFORMING CATALYST AT A TEMPERATURE BETWEEN ABOUT 800 AND 1000* F. AND A PRESSURE BETWEEN ABOUT 50 AND 750 P.S.I.G. AND COMBINING THE REFORMED LIQUID PRODUCT WITH SAID LIGHT FRACTION TO PRODUCE A MOTOR FUEL OF HIGH OCTANE NUMBER. 